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Wyświetlanie 1-15 z 63
Tytuł:
[100] Loading of Fcc Based Nanofibre Reinforced Composites
Autorzy:
Černý, M.
Pokluda, J.
Powiązania:
https://bibliotekanauki.pl/articles/1418509.pdf
Data publikacji:
2012-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.46.Km
62.20.D-
62.23.Pq
68.35.bd
81.05.Ni
Opis:
Ab initio calculations of theoretical tensile and compressive strengths in the 〈100〉 direction of a composite having continuous nanofibre reinforcements are performed using pseudopotential approach within density functional theory. Results for iridium or platinum nanofibres in copper or gold matrices, presented as case studies, reveal that the theoretical tensile and compressive strengths almost linearly increase with increasing atomic concentration of the reinforcement exhibiting only slight positive strength deviations from the linearity for Pt-Au and slight negative deviations of the tensile strength for Ir-Cu.
Źródło:
Acta Physica Polonica A; 2012, 122, 3; 505-508
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
AC Magnetic Properties of Vitroperm Based Composite Materials
Autorzy:
Kollár, P.
Hegedüs, L.
Füzer, J.
Bureš, R.
Fáberová, M.
Powiązania:
https://bibliotekanauki.pl/articles/1533956.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Tt
81.05.Ni
85.70.-w
75.60.-d
75.50.Bb
Opis:
The aim of this work was to investigate the influence of resin content on AC magnetic properties of Vitroperm 800-based composite material to extend possibilities for application of this kind of material at higher frequency (up to 100 kHz). The samples of composite material were prepared in the form of the ring with outer diameter of 25 mm, inner diameter of 18 mm and height approximately 3 mm. Powder mixtures were prepared from Vitroperm 800 in partial nanocrystalline state and commercial termoset resins by mechanical mixing. The AC magnetic properties (losses) at maximum induction up to 0.5 T were measured by MATS-2010SA loop tracer in frequency range 1-100 kHz. The specific resistivity of the material was measured by the van der Pauw method. The magnetic properties of the composite rings were compared with the properties of the material prepared from Fe based powder supported by Höganäs. It was found out that the total losses of the Vitroperm-based soft magnetic composite are more than 10 times lower (at 10 kHz) than that for Fe-based one.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 787-789
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
AFM/STM Modification of Thin Sb Films on 6H-SiC(0001)
Autorzy:
Mazur, P.
Zuber, S.
Grodzicki, M.
Ciszewski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1195467.pdf
Data publikacji:
2014-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Dz
68.37.Ps
68.37.Ef
68.37.-d
81.10.Bk
81.07.-b
Opis:
Atomic force microscopy and scanning tunneling microscopy have been used for nanometer scale modifications of Sb films deposited on 6H-SiC(0001) surface. The films are grown in situ by vapor deposition under ultrahigh vacuum. The growth follows the Volmer-Weber mode. Ultrathin (up to 3 nm on average) Sb films which consist of no coalesced islands can be modified by moving the island over the substrate surface by the AFM tip. Thicker films, which are firmer due to the coalescence, can be modified by the field and/or current produced by STM tip. Final result of the modifications is adsorbate free 6H-SiC(0001) surface restitution over the modified area.
Źródło:
Acta Physica Polonica A; 2014, 126, 5; 1131-1133
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of a Skid Type Landing Gear of a Rotary Wing UAV by Experimental and Numerical Methods
Autorzy:
Yildirim, O.
Günay, E.
Anil, Ö.
Aygün, C.
Powiązania:
https://bibliotekanauki.pl/articles/1401314.pdf
Data publikacji:
2015-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Bx
45.20.da
45.50.Tn
02.70.Dh
04.80.Cc
06.30.-k
45.20.D
Opis:
The objective of this study was to analyze the results obtained from tests done by simulating the crash landing of a rotary wing unmanned air vehicle with a skid type landing gear. The experimental and computational methods were used in the simulation tests. In the first portion of the test; namely with the experimental method, the impact loads induced by the simulated crash landing and the stresses, strains, deformations generated by these loads, were recorded by drop test apparatus. In the second portion of the test with the computational method, free falling of the skid type landing gear was modeled and crash landing test was simulated numerically by using ANSYS code. Experimental methods were applied on four skid landing gear specimens with different shapes. Each of the test samples used in the following test was evolved because each sample was developed and redesigned based on the feedback results obtained from the former test.The first three test specimens were manufactured from 2024 T3, 7075 T6 and 6061 T6 aluminum alloys respectively and all of them were curved in Π-form with a solid cross section. The last and fourth specimen was also manufactured from 6061 T6 aluminum alloy and it was curved in a hollow semi-circle form (∩-form). It is concluded that the last and fourth developed specimen was the best in absorbing the impact energy and enduring the crash.
Źródło:
Acta Physica Polonica A; 2015, 127, 4; 1170-1175
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Anion Removal Potential of Complex Metal Oxides Estimated from Their Atomic Scale Structural Properties
Autorzy:
Chubar, N.
Gerda, V.
Mičušík, M.
Omastova, M.
Heister, K.
Man, P.
Yablokova, G.
Banerjee, D.
Fraissard, J.
Powiązania:
https://bibliotekanauki.pl/articles/1030882.pdf
Data publikacji:
2018-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Je
81.05.Rm
68.43.-h
82.80.-d
Opis:
The main common idea of two conference papers delivered at OMEE-2017 was to demonstrate an importance of the speciation level knowledge in modern adsorption materials science. In order to prove this, two groups of adsorptive materials were used: three samples of Mg-Al-CO₃ layered double hydroxides produced by different synthesis methods and ten samples of Fe-Ce oxide-based composites with various ratios of Fe-to-Ce. In both cases of studies, it was not possible to find direct correlation between adsorptive performances of the materials and their structural properties obtained by conventional characterisation techniques. However, anion adsorptive removals of each group of inorganic composites correlated with their structural properties studied on the level of speciation. It was shown that strong anion removal potential of Mg-Al-CO₃ layered double hydroxides was associated with richness in speciation of chemical elements (Mg, Al) and interlayer anions (CO₃²¯) as well as with generous hydration. Adsorptive performances of inorganic anion exchangers based on Fe-Ce hydrous oxides were explained by simulation extended X-ray absorption fine structures simulation. The best anion removers were found to be those Fe/Ce oxide-based composites whose Fe outer shells were formed from backscattering oscillations from both O and Fe atoms.
Źródło:
Acta Physica Polonica A; 2018, 133, 4; 1091-1096
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Extended Jiles-Atherton Model for Modelling the Influence of Stresses on Magnetic Characteristics of the Construction Steel
Autorzy:
Jackiewicz, D.
Szewczyk, R.
Salach, J.
Bieńkowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1202331.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.60.Ej
75.60.-d
81.70.-q
Opis:
Paper presents the possibility of application of the Jiles-Atherton extended model to describe the magnetic characteristics of construction steel C45 under the influence of tensile stresses. Experiment was performed on the frame-shaped samples. Then, the influence of stresses on hysteresis loops was modelled with the Jiles-Atherton extended model. The obtained results of the modelling are consistent with results of the experimental measurements. The results of modelling create new possibilities of explanation of the physical phenomena connected with magnetisation of the magnetic materials under stresses, which is esential for the assessment of the state of the construction steel during its exploitation in industrial conditions.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 392-393
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of High Permittivity Bismuth Copper Titanate in Multilayer Capacitors
Autorzy:
Szwagierczak, D.
Kulawik, J.
Powiązania:
https://bibliotekanauki.pl/articles/1490915.pdf
Data publikacji:
2012-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
77.22.-d
81.20.-n
84.32.Tt
85.40.Xx
Opis:
A nonferroelectric high permittivity compound with the perovskite structure, $Bi_{2//3}Cu_3Ti_4O_{12}$, was synthesized at 900°C. The ceramic powder and appropriate organic additives were used for preparation of a slurry for tape casting. The obtained green tapes were smooth, flexible, and with a uniform thickness of 25 μm after drying at 50°C. Ag electrodes were screen printed on green rectangular sheets cut by a laser. Subsequent operations were screen printing of Ag internal electrodes, stacking of green sheets, isostatic lamination, cutting, deposition of external terminations and co-firing of dielectric and conductive layers at 850°C. Scanning electron microscopy observations showed well sintered, dense, fine-grained microstructure of ceramic layers and good cooperation with the electrodes made of commercial Ag paste. Capacitance and dissipation factor of multilayer capacitors were examined in the temperature range from - 55 to 330C at frequencies 10 Hz-2 MHz. The fabricated multilayer capacitors exhibit high capacitance and relatively low temperature coefficient of capacitance in the temperature range from - 55 to 110°C. The obtained lead-free high permittivity nonferroelectric material $Bi_{2//3}Cu_3Ti_4O_{12}$ is a spontaneously formed internal barrier capacitor. This material seems to be a promising alternative for conventional lead-based relaxor dielectrics in multilayer ceramic capacitors.
Źródło:
Acta Physica Polonica A; 2012, 121, 1; 119-121
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Armaty czołgowe rodziny D-81 kalibru 125 mm
Autorzy:
Przeździecki, Paweł (1981- ).
Powiązania:
Nowa Technika Wojskowa 2021, nr 5, s. 26-33 ; 2021, nr 6, s. 24-31
Data publikacji:
2021
Tematy:
Armaty czołgowe
D-81 (armata)
Budowa i konstrukcje
Dane taktyczno-techniczne sprzętu wojskowego
Modernizacja
Amunicja
Artykuł z czasopisma wojskowego
Artykuł z czasopisma fachowego
Opis:
Artykuł dotyczył radzieckiej armaty czołgowej D-81 kalibru 125 mm. Opisano genezę jej powstania, konstrukcję oraz dane taktyczno-techniczne. Omówiono trzy kolejne modernizacje tej armaty. Przedstawiono armaty D-81 produkowane na licencji w innych krajach m.in. w Czechosłowacji, Ukrainie i w Chinach. Opisano także amunicję do tej armaty produkowaną w ZSRR i w Federacji Rosyjskiej.
[Cz. 1-2].
Dostawca treści:
Bibliografia CBW
Artykuł
Tytuł:
Channeling Study of Co and Mn Implanted and Thermally Annealed Wide Band-Gap Semiconducting Compounds
Autorzy:
Ratajczak, R.
Werner, Z.
Barlak, M.
Pochrybniak, C.
Stonert, A.
Zhao, Q.
Powiązania:
https://bibliotekanauki.pl/articles/1402209.pdf
Data publikacji:
2015-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.43.-j
61.72.-y
81.05.-t
82.80.-d
85.40.-e
Opis:
The defect build-up, structure recovery and lattice location of transition metals in ion bombarded and thermally annealed ZnO and GaN single crystals were studied by channeled Rutherford backscattering spectrometry and channeled particle-induced X-ray emission measurements using 1.57 MeV ⁴He ions. Ion implantation to a fluence of 1.2×10¹⁶ ions/cm² was performed using 120 keV Co and 120 keV Mn ions. Thermal annealing was performed at 800°C in argon flow. Damage distributions were determined using the Monte Carlo McChasy simulation code. The simulations of channeled Rutherford backscattering spectra reveal that the ion implantation leads to formation of two types of defect structures in ZnO and GaN such as point and extended defects, such as dislocations. The concentrations of both types of defects are at a comparable level in both structures and for both implanted ions. Differences between both implantations appear after thermal annealing where the Mn-doped ZnO reveals much better transition metals substitution and recovery effect.
Źródło:
Acta Physica Polonica A; 2015, 128, 5; 845-848
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Magnetosomes After Exposure to the Effect of the Sonication and Ultracentrifugation
Autorzy:
Molčan, M.
Hashim, A.
Kováč, J.
Rajňák, M.
Kopčanský, P.
Makowski, M.
Gojzewski, H.
Molokáč, M.
Hvizdák, L.
Timko, M.
Powiązania:
https://bibliotekanauki.pl/articles/1368025.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.07.-b
75.60.-d
87.50.Y-
68.37.-d
Opis:
Magnetosomes are intracellular organelles of widespread aquatic microorganisms called Magnetotactic bacteria. At present they are under investigation especially in biomedical applications. This ability depends on the presence of intracellular magnetosomes which are composed of two parts: first, nanometer-sized magnetite $(Fe_{3}O_{4})$ or greigite $(Fe_{3}S_{4})$ crystals (magnetosome crystal), depending on the bacterial species; and second, the bilayer membrane surrounding the crystal (magnetosome membrane). The magnetosomes were prepared by biomineralization process of magnetotactic bacteria Magnetospirillum Magnetotacticum sp. AMB-1. The isolated magnetosome chains (sample M) were centrifugated at speed of 100000 rpm for 4 hours (sample UM) and sonicated at power of 120 W for 3 hours (sample SM), respectively. The prepared suspensions were investigated with respect to morphological, structural and magnetic properties. The results from scanning electron microscopy showed that isolated chains of magnetosomes were partially broken to smaller ones after ultracentrifugation. On the other hand the application of the sonication process caused the formation of individual magnetosomes (unordered in chain). These results were confirmed by coercivity and magnetization saturation measurements.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 198-199
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of Five-Layered ZrO₂ and Single-Layered Ce, Eu, and Dy-Doped ZrO₂ Thin Films Prepared by Sol-Gel Spin Coating Method
Autorzy:
Çiçek Bezir, N.
Evcin, A.
Kayali, R.
Özen, M.
Esen, K.
Powiązania:
https://bibliotekanauki.pl/articles/1031178.pdf
Data publikacji:
2017-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.37.-d
68.55-a
68.60-p
78.20.-e
81.10.Dn
71.20.Be
Opis:
In order to investigate the influence of the number of layers on the properties of ZrO₂ thin films, we prepared one pure ZrO₂ film sample with five layers and Ce, Eu, and Dy-doped ZrO₂ samples with single layer, by spin-coating sol gel-method. The crystal structures of thin films were determined using X-ray diffraction, morphology of the samples was analyzed by scanning electron microscopy, and the optical properties of the samples were determined by ultraviolet/visible absorbance measurements. The results of these measurements have shown that the concentration of the dopants and the thickness of thin film layers play a vital role in the physical, chemical, and optical properties of the pure and doped ZrO₂ thin films.
Źródło:
Acta Physica Polonica A; 2017, 132, 3; 612-616
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of Pure and Doped TiO₂ Thin Films Prepared by Sol-Gel Spin-Coating Method
Autorzy:
Çiçek Bezir, N.
Evcin, A.
Kayali, R.
Özen, M.
Balyaci, G.
Powiązania:
https://bibliotekanauki.pl/articles/1031525.pdf
Data publikacji:
2017-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.37.-d
68.55.-a
68.60.-p
78.20.-e
81.10.Dn
71.20.Be
Opis:
In this study, using spin-coating sol-gel method we fabricated TiO₂ thin films, doped with different concentrations (1, 2, and 3 mole %) of Ce, Dy, and Eu. Characterization of the prepared samples was performed by means of the X-ray diffraction, scanning electron microscopy, ultraviolet visible absorption, and differential thermal and thermo gravimetric analysis. X-ray diffraction measurements have shown that in Eu and Dy-doped samples crystal structure consists of mixed rutile and the dominant anatase phases, however the Ce doped samples consist of anatase phase only. Scanning electron microscopy images have revealed that while average thin film thickness of the Dy-doped samples decreases with increasing concentration of Dy, the average film thicknesses of samples doped with Ce and Eu increases with increasing concentrations of these dopants. Ultraviolet visible absorption spectroscopy measurements have shown that while absorbances of the samples doped by 1 and 2 mole % of the dopants have nearly similar properties, these properties differ from each other for 3 mole % of the dopants. Finally, differential thermal and thermo gravimetric analyses have shown that the chemical reactions and weight losses of the samples have occurred at the expected temperatures.
Źródło:
Acta Physica Polonica A; 2017, 132, 3; 620-624
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Defect Transformations in Ion Bombarded InGaAsP
Autorzy:
Ratajczak, R.
Turos, A.
Stonert, A.
Nowicki, L.
Strupiński, W.
Powiązania:
https://bibliotekanauki.pl/articles/1504046.pdf
Data publikacji:
2011-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.43.-j
61.72.-y
81.05.-t
82.80.-d
85.40.-e
Opis:
Damage buildup and defect transformations at temperatures ranging from 15 K to 300 K in ion bombarded InGaAsP epitaxial layers on InP were studied by in situ Rutherford backscattering/channeling measurements using 1.4 MeV $\text{}^4He$ ions. Ion bombardment was performed using 150 keV N ions and 580 keV As ions to fluences ranging from 5 × $10^{12}$ to 6 × $10^{14}$ at./$cm^2$. Damage distributions were determined using the McChasy Monte Carlo simulation code assuming that they consist of randomly displaced lattice atoms and extended defects producing bending of atomic planes. Steep damage buildup up to amorphisation with increasing ion fluence was observed. Defect production rate increases with the ion mass and decreases with the implantation temperature. Parameters of damage buildup were evaluated in the frame of the multi-step damage accumulation model. Following ion bombardment at 15 K defect transformations upon warming up to 300 K have also been studied. Defect migration beginning above 100 K was revealed leading to a broad defect recovery stage with the activation energy of 0.1 eV for randomly displaced atoms and 0.15 eV for bent channels defects.
Źródło:
Acta Physica Polonica A; 2011, 120, 1; 136-139
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Argon Plasma on the Float Glass Surface
Autorzy:
Tuleta, M.
Powiązania:
https://bibliotekanauki.pl/articles/1503946.pdf
Data publikacji:
2011-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Kf
52.77.-j
82.80.-d
Opis:
Both surfaces of a commercial float glass were treated simultaneously by a low-temperature argon plasma generated by an inductively coupled rf power supply. The effect of plasma processing on the outer surface composition of both sides of the glass was analysed by means of the ion scattering spectroscopy technique. The observed recomposition of the outer surface atoms was interpreted as a result of the action of the thermal and electric fields created by the plasma on particular glass constituents.
Źródło:
Acta Physica Polonica A; 2011, 120, 1; 91-93
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Borax Pentahydrate Addition to Acid Bath on the Microstructure and Corrosion Resistance of Zn-Co Coating
Autorzy:
Karahan, İ.
Powiązania:
https://bibliotekanauki.pl/articles/1402495.pdf
Data publikacji:
2015-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.37.-d
68.55.-a
81.65.Kn
Opis:
In this work, the Zn-Co coatings were synthesized on AISI 4140 steel and aluminum plates by using potentiostatic electrodeposition technique in sulphate-based acidic baths with 0, 20, 40 and 60 gl¯¹ of borax pentahydrate, as additive. The effect of borax pentahydrate on the microstructure of the samples was observed using scanning electron microscopy and X-ray diffractometer. The deposition process was investigated by cyclic voltammetry. The effect of borax pentahydrate on the corrosion resistance of the samples was studied by potentiodynamic polarization technique. The results have demonstrated, that the addition of borax pentahydrate was in favor of the growth of grains. The morphology of pyramidal islands on the surface was changed to a more flat structure. The results have also demonstrated that the effect of borax pentahydrate was not monotonous. With increasing concentration, the corrosion potential was at minimum and the charge transfer resistance $R_{t}$ was at maximum for the sample obtained from the bath with 60 gl¯¹ of borax pentahydate, indicating that this sample showed the best corrosion resistance. It was found that current density first decreased and than increased, due to adsorption of a complex of borax pentahydrate and/or changes in the morphology, however, the initial deposition potential was not affected. The addition of borax pentahydrate to the bath led to formation of the best Zn-Co deposits, composed of coalesced globular fine grains, smaller than ≈2 μm in diameter. In addition, all of the studied Zn-Co deposits consisted of η phases. It is suggested that Zn-Co deposits produced in the bath containing 60 gl¯¹ of borax pentahydrate probably offer sacrificial protection to the steel substrate.
Źródło:
Acta Physica Polonica A; 2015, 128, 2B; B-432-B-435
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 63

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